Input sensing method and input sensing device including the same

Abstract

An input sensing device includes: sensor pixels, a horizontal driver, a selection circuit, and a vertical driver. Each of the sensor pixels is connected to a plurality of driving lines and a one of a plurality of signal input lines. The horizontal driver sequentially applies a horizontal driving signal to the sensor pixels through the driving lines. The selection circuit is connected to n of the signal input lines (n is a natural number of 2 or more) and to one output line. The selection circuit sequentially outputs n sensing signals received through the n signal input lines to the one output line. The vertical driver receives the n sensing signals through the one output line. The horizontal driver applies the horizontal driving signal n times to a given one of the driving lines to correspond to the n sensing signals.

What is claimed is: 
     
       1. An input sensing device comprising:
 a plurality of sensor pixels, where each sensor pixel is connected to a corresponding one of a plurality of driving lines and a corresponding one of a plurality of signal input lines; 
 a horizontal driver configured to sequentially apply a horizontal driving signal to the plurality of sensor pixels through the driving lines; 
 a selection circuit connected to n of the signal input lines and to one output line, the selection circuit configured to sequentially output n sensing signals received through the n signal input lines to the one output line, where n is a natural number of 2 or more and the selection circuit includes n selection transistors connected between the n signal input lines and the one output line; and 
 a vertical driver configured to receive the n sensing signals through the one output line, 
 wherein the horizontal driver applies the horizontal driving signal to a given one of the driving lines n times to correspond to the n sensing signals, 
 wherein each of n sensor pixels among the sensor pixels include a pixel transistor connected to a corresponding one of the n signal input lines, and 
 during each of n sequential periods of part of a sensing period, the n times of the horizontal driving signal of a gate-on voltage level is applied to the given one driving line to turn on the pixel transistor of one of the n sensor pixels while a sensing signal control signal is applied to turn on a corresponding one of the n selection transistors, 
 wherein the vertical driver comprises: 
 an integration circuit for integrating a corresponding one of the sensing signals to generate a first output signal; 
 an analog-to-digital converter that converts the first output signal of an analog type into a sensing data signal of a digital type; and 
 a correlated double sampling circuit disposed between an output terminal of the integration circuit and the analog-to-digital converter, 
 wherein the correlated double sampling circuit comprises: 
 a first sampling switch disposed between the output terminal and the analog-to-digital converter; 
 a second sampling switch disposed between the output terminal and the analog-to-digital converter; 
 a first sampling capacitor including one terminal connected between the first sampling switch and the analog-to-digital converter; 
 a second sampling capacitor including one terminal connected between the second sampling switch and the analog-to-digital converter; and 
 a differential amplifier including a first input terminal connected to one terminal of the first sampling capacitor, a second input terminal connected to one terminal of the second sampling capacitor, and an output terminal, and 
 wherein each of the n selection transistors is turned on before the first sampling switch is turned on, and is turned off after the second sampling switch is turned off. 
 
     
     
       2. The input sensing device of  claim 1 , wherein the integration circuit comprises:
 an amplifier including a first input terminal connected to the output line, a second input terminal connected to a reference voltage line, and an output terminal; 
 a capacitor including a first electrode connected to the first input terminal and a second electrode connected to the output terminal; and 
 an initialization switch disposed between the first input terminal and the output terminal. 
 
     
     
       3. The input sensing device of  claim 2 , wherein the correlated double sampling circuit turns on the first sampling switch before the horizontal driving signal is applied to store a (1_1)-th output signal in the first sampling capacitor, and turns on the second sampling switch after the horizontal driving signal is applied to store a (1_2)-th output signal in the second sampling capacitor, and the differential amplifier outputs a (1_3)-th output signal by differentiating the (1_1)-th output signal and the (1_2)-th output signal. 
     
     
       4. The input sensing device of  claim 2 , wherein the amplifier turns on the initialization switch before turning on the first sampling switch. 
     
     
       5. The input sensing device of  claim 2 , wherein each of the n selection transistors is turned on before the initialization switch is turned on. 
     
     
       6. The input sensing device of  claim 1 , wherein the horizontal driving signal is applied n times to each driving line. 
     
     
       7. The input sensing device of  claim 1 , wherein at least one of the plurality of sensor pixels is further connected to a reset voltage power line, a bias voltage power line, and a common voltage power line. 
     
     
       8. The input sensing device of  claim 7 , further comprising:
 a reset circuit that is connected to the plurality of sensor pixels and a reset signal control line and simultaneously applies a reset voltage to the plurality of sensor pixels. 
 
     
     
       9. The input sensing device of  claim 8 , wherein at least one of the plurality of sensor pixels comprises:
 a first transistor including a first electrode connected to the reset voltage power source, a second electrode connected to a first node, and a gate electrode connected to the reset signal control line; 
 a photodiode including an anode electrode connected to the bias voltage power line and a cathode electrode connected to the first node; 
 a second transistor including a first electrode connected to the common voltage power line, a second electrode connected to a second node, and a gate electrode connected to the first node; and 
 the pixel transistor including a first electrode connected to the second node, a second electrode connected to the signal input line, and a gate electrode connected to the driving line. 
 
     
     
       10. The input sensing device of  claim 9 , wherein the sensor pixel further includes a capacitor including a first electrode connected to the bias voltage power line and a second electrode connected to the first node.